Construction and application of hydrophilic magnetic molecularly imprinted polymers for the analysis of sulfamethoxazole.

Sulfamethoxazole (SMX) is a widely used toxic and persistent antibiotic, and its residues in water environments pose potential health risks. Interfering substances in complex matrices seriously affect its accurate detection. In this study, hydrophilic magnetic molecularly imprinted polymers were synthesized, which were combined with ultra-high-performance liquid chromatography-tandem mass spectrometry to selectively enrich and detect SMX in environmental water and aquatic products. A series of characterization tests verified the successful fabrication of the material. The adsorption complied with the Langmuir monolayer model and pseudo-second-order kinetic model. The LODs were 0.018-0.045 ng mL-1 for water and 0.057-0.085 µg kg-1 for aquatic products, and the LOQs were 0.06-0.15 ng mL-1 and 0.19-0.28 µg kg-1, respectively. Spiked recoveries ranged from 90.2% to 109.6% in water and 98.1% to 101.1% in aquatic products. Glycidyl methacrylate modification improved the material's anti-fouling performance. This method realizes sensitive trace SMX detection and helps guarantee aquatic ecological and food safety.